Automatic gas cut-off



Nov. 27,1934. F. RAiBLE I AUTOMATIC GAS GUT-OF!l Filed Aug. 4. 1951 Patented Nov. 27, 1934 UNITED STATES PATENT lOFFICE 1,082,481 i su'rom'rxo Gas cU'r-orr E man wie, unisa, Germany Application Auna 4, im, serai No. 555,069

ln'Getmany June 2991931v z claim. (ci. iss-111.2)

invention relates to a device for gas cookers, designed to automatically close, by a thermostat, the gas cock when the gas flame is extinguished. According to the invention the cock plug must be lifted, in order to establish the gas admission, and a locking rod connected with the thermostat is adapted to penetrate when this thermostat is being heated into a horizontal 1ncision in the cock plug to hold the plug in the raised position until the thermostat withdraws from said incision owing to the cooling of the lever system. The incision in the cock plug is of such depth that the plug canbe turned in the locked position, the ilowing through of gas being possible only in this position, so that the quantity of gas can be regulated.

- An embodiment of the invention is illustrated by way of example in the accompanying drawing, in which:

Fig. 1 shows the device in longitudinal section, partly in side elevation. in the operative position.

Fig. 2 is a horizontal section, partly in plan view on line II-II of Fig. 1.

Fig. 3 is a horizontal part section on line IH-IlI of Fig.V 1.

Fig. 4 is a cross section on line IV-IV of Fig. 1.

A piston-like plug b is inserted in a cylindrical cock housing a so that it can be raised a certain distance and V is adapted. to automatically drop back by gravity into the initial position. The gas passage c is arranged in the plug b so that the gas supply to the-burner can take place only ii' the plug is raised and has been turned accordingly. When the plug is in the lower or inoperative position, communication with the gas tube and burner cannot be produced even by turning the plug.

The plug b has a handle d, by means oi which it can be raised. The lower portion of the plug ilts gas-tightly into the housing a. In order to allow escaping of theair from the casing when the plug is being 1owered,\ an air hole ck is provided in the bottom plate of the housing. The upper portion b' of the plug is slightly turned oi and has a horizontal incision f. In the housing wall a hole g is arranged at such height that it registers with the incision f of the plug when this plug is raised.

The stroke oi the plug is limited by a shoulder b2 on the plug. and by a screwxcap screwed on the upperend oi' the housing a. A locking rod h, engaging with the hole g, is connected to a thermostat. This thermostat consists of a metal strip i and of a heat transmitting strip k. On the gas tube q of the gas cooker a device is iixed which consists ot a clip l, a plate 1n and two vertical sleeves n fixed on said plate. These sleeves n are slit and the ends of the metal strip i are inserted one in each sleeve n. The device is covered by a curved hood o having two downwardly extending slit sleeves p, arranged so that they can engage over the sleeves n which h old the metal strips i. 'Ihe hood o is designed to protect the thermostat against soiling and against liquids which might flow over i'rornA pots or pans. At the middle of the metal strip i the corresponding end oi the heat transmission strip k is folded .over the metal strip and its free end is bent twice to form a bow extending into the gas flame and designed to conduct the heat to the thermostat i. The thermostat i is adjusted on the gas tube q and ilxed on the same by the pipe clip I in such la position that the bowshaped portion of the heat transmitting strip k is within the range of the gas flame of the gas cooker r. f The portion of the heat conducting strip k, which is folded over the thermostat strip i has an extension k', carrying a stud s. A lever u pivotally mounted on a base plate m by means of a. pivot pin t engages over said stud s. The locking rod h is hingedly connected to the outer end of the lever u.

The thermostat strip i bulges in the direction towards the gas cock under the action ofthe heat transmitted by the heat conducting strip k, and this heat conductor moves together with this bulging out portion of the thermostat. Through the stud s of the arm k of the heat conductor k the lever u is oscillated and pushes by its end the locking rod Ii.l into the incision f of the cock plug. The transmission of the movement of the thertmostat 1' by the lever arm u serves to eilect a rapid engagement oi' the locking rod h into the incision f of the cock plug, as this plug has to be held inthe raised position by hand until the locking by rod h has been effected. If the cock plug would be released prematurely, it would drop and shut off the gas admission. It takes about 10 seconds, before the rod h locks the cock plug when the gas is ignited. On the cock housing a.a locking pawl v may be arranged, designed to engage with its nose i under the handle d of the cock plug, when this plug is in the raised position. On the rod h an abutment w is then provided which, when the locking rod' h moves forward, strikes against the locking pawl v and makes the same oscillate as soon as the locking rod has engaged in the incision of the plug, so that the nose a releases the handle d. The locking rod prevents the plug from dropping as long as the gas flame is not extinguished. After the gas flame ,has been extinguished, the metal strip i returns into its stretched position, whereby the locking rod h is withdrawn from the incision f so that the plug is released, drops and shuts off the gas passage.

The incision f extends over more than half the circumference of the cock plug b so that this cock plug can be turned in the raised position, even when the locking rod h engages with the incision f, so that the gas flow can be regulated or shut off entirely.

The open position of the cock plug is indicated on the handle d as usual. The middle of the incision` f is opposite the locking rod h, as shown in Fig. 2, and the bore or passage c in the plug is in alignment with the gas tubes as shown in Fig. 3. The main burner' is supplied with gas through the bore c, and the small burner of the gas cooker for the by-pass flame is supplied with gas through a narrow annular groove 2:, extending over half` the circumference of the gas plug, and through a supply tube y of small diameter. The gas supply to the main burner isvregulated by the cock plug being turned to the right or to the left, the incision f permitting the turning of the plug through 90 to the right or to the left. Both extreme positions are limited by the engaging locking rod h. When the cock plug is in the extreme right hand position, the passage c for the main burner is completely shut off, only the gas supply for the small burner being open through the annular channel a: so that only the by-pass ame is burning. If the cock plug is in the extreme left hand position, the main gas supply and also the gas supply for the by-pass flame are shut oil, so that both flames extinguish, the thermostat cools and withdraws the locking rod h, whereupon the cock plug drops into the inoperative position.

I claim:-

1. In combination with a gas burner, a selfclosing cock having a hollow cylindrical housing with a bottom, the lower part of said housing having two mutually opposite .bores for the passage of the gas and the upper part having a hole in its wall, a plug in said housing resting on the bottom of said housing, the lower part of said plug fitting gas-tightly in said housing and having a gas passage and the upper part reduced in diameter and havingA a radial incision, said plug being liftable in said housing to bring its gas passage into alignment with the gas passage in said housing and its incision into alignment with said hole of the housing, and said plug also rotatable for the purpose of regulating the gas ow through the gas passages in said housing and said plug when the latter is lifted, a rod penetrating into the hole in said housing, thermostatic means positioned Within heating relation to the burner and operable to shift said rod into said incision in the plug, when the latter is lifted, a handle on said plug, a pawl operating to engage under said handle when said plug is in lifted position, and a catch on said rod operating to disengage said pawl when said rod is shifted into the incision in said plug.

2. In combination with a gas burner, a selfclosing cock having a hollow cylindrical housing with a bottom, the lower part of said housing having two mutually opposite bores for the passage of the gas and the upper part. having a hole in its wall, a plug in said housing. resting on the bottom of said housing, the lower part of said plug fitting gas-tightly in said housing and having a gas passage and the upper part of said plug having a radial incision, said plug being liftable in said housing to bring its gas passage into alignment wth the gas passage in said housing and its incision into alignment with said hole of the housing, and said plug also being rotatable for the purpose of regulating the gas ow through the gas passages of the housing and the plug, when the lat'ter is lifted, a locking rod penetrating into the hole in said housing, a thermostatic metal strip, two sleeves fixed to the burner, slits in said sleeves, the ends of the thermostatic metal strip being inserted into the splits of said sleeves, a hood, two downwardly directed sleeves on said hood positioned to engage over said sleeves on the burner, a strip of heat conducting material folded over the middle of said thermostatic metal strip and bent at one end to forma bow situated within the range of the gas flame, an extension of the folded portion of said heat conducting material, said locking rod being connected,with said extension of heat conducting material and operable to be shifted into said radial incision of said plug by said thermostatic metal strip when heated.

- FRANZ RAIBLE. 

